Musical tones from acoustic bowed string and wind instruments, though nearly periodic, have a noise component that is a subtle but crucial part of the sound. Prior art attempts to simulate these instruments in digital electronic synthesizers have been deficient with regard to the exact quality of the noise component.
The present invention is based on a new description or model of the noise generation mechanism in bowed string and wind instruments (including brass and voice) which accounts for some of the noise present in self-sustained mechanical oscillators (i.e., non-percussive acoustical musical instruments). Analyses by the inventor have verified the existence of the noise predicted by this new model, and digital simulations using the present invention have synthesized tones with improved bow and breath noise. The present invention is particularly applicable to bowed string instruments such as the violin, cello, and bass, and to wind instruments such as the clarinet, oboe, flute, trumpet, trombone and the human voice.
The precise quality of the noise generated when synthesizing the tones of bowed strings and wind instruments is important in achieving an improved sound synthesis capability. Mixing in spectrally shaped Gaussian noise has not proved sufficient. There is no perceptual fusion of the noise and periodic sounds, and the listener hears two sources. A subjective impression from the best attempts to mix in spectrally shaped Gaussian noise is that the noise is "not well-incorporated." Though this is not a common evaluation in acoustic parlance, the meaning of this subjective analysis will become evident from the following description of the present invention.